Cancer is found in the cervix only. Stage I is divided into stages IA and IB, based on the amount of cancer that is found. In stage IA, a very small amount of cancer that can only be seen with a microscope is found in the tissues of the cervix. The cancer is not deeper than 5 millimeters and not wider than 7 millimeters. In stage IB, the cancer is still within the cervix and either (1) can only be seen with a microscope and is deeper than 5 millimeters or wider than 7 millimeters; or (2) can be seen without a microscope and may be larger than 4 centimeters.